The CrashPlan app uses file watching services to monitor your Mac computer for file changes. This article describes:
- The technical details about how the CrashPlan app and file watching services work together
- Recommended solutions for errors associated with file watching services
How the CrashPlan app uses file watching services
At a high level, here's how the CrashPlan app coordinates with Mac file watching services to back up your new or changed files:
- The CrashPlan app starts to back up.
- The CrashPlan app requests a snapshot from the file watching service for all local drives using File System Events.
- The file watching service creates a snapshot containing information on all new or changed files.
- The file watching service provides the CrashPlan app with details to access the new snapshot.
- The CrashPlan app backs up ALL files using the snapshot until it reaches a file that has changed since the snapshot was created or the backup session finishes.
This process repeats when the file watching service reports data in your file selection has changed.
Diagnose problems with file watching services
If your backup never reaches 100%, or you see the message "unable to back up n files" in your History.log file, you can check your logs to find the files that are not backing up.
The reason may be due to one of the following file watcher-related problems:
Unable to back up files due to restricted permissions
The CrashPlan app cannot back up files or folders that have restricted permissions and display a red circle in the Finder. You can either prevent CrashPlan app from trying to back up the files by modifying your file selection, or you can perform the following steps to change permissions on the files to allow the CrashPlan app read/write access:
- In Finder, select the folder you want to update.
- Choose File > Get Info.
- Click the triangle next to Sharing & Permissions to expand the section.
- Click the lock icon to allow editing of your settings.
- When prompted, enter your password to allow changes to the Finder.
- Next to everyone, click No Access to display privilege options.
- Select Read & Write.
- Click the gear icon, then select Apply to enclosed items to apply the setting to enclosed subfolders and files.
Click OK when prompted to confirm the change.
- Click the lock icon again to prevent future changes.
CrashPlan app is unaware of file changes
Because the CrashPlan app uses a file watching service to detect file changes, the CrashPlan app real-time file watch feature cannot detect any new or changed files in your file selection if the file watching service does not report the changes to the files. Confirm that the file watching service is reporting file changes:
- Manually start the file verification process in the CrashPlan app by selecting Scan for file changes.
- Apple: Spotlight Overview
- Apple: How to re-index Spotlight
- Apple: File System Events